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Story highlights

Marco Rubio's campaign is preparing for a contested Republican Convention as one option to take the GOP nomination away from Donald Trump and Ted Cruz

He outlined the plans to a closed-door meeting of GOP donors in New York

Watch CNN’s Republican debate live on Thursday at 8:30 p.m. ET.

Houston CNN —  

Marco Rubio’s campaign is preparing for a contested Republican Convention as one option to take the GOP nomination away from Donald Trump and Ted Cruz, his campaign manager told top donors at a closed-door meeting in Manhattan Wednesday night.

Marco Rubio super PAC hits Super Tuesday airwaves without rivals

As Rubio scrambles for support ahead of Super Tuesday, Terry Sullivan, Rubio’s top adviser, used a Power Point presentation and took questions from attendees to lay out the two courses that Rubio’s quest for the GOP nomination could take in the coming months, two people present told CNN, speaking anonymously to share details from a private meeting.

Everything changes March 1

The first showed the number of states and delegates Rubio would need to clinch the nomination outright before July’s convention. The second was the scenario in which none of the candidates gain the simple majority delegates needed to clinch the nomination before the convention, unleashing a messy and potentially unpredictable battle where multiple candidates are vying for the title.

The meeting comes as Rubio is trying to lock up the support of establishment Republicans looking for an alternative to Trump and Cruz. The Rubio campaign needs to convince donors and GOP power brokers that it has a true path to victory. Trump is heading into Super Tuesday as the undisputed GOP front-runner, having won New Hampshire, South Carolina and Nevada, and Rubio has not yet won a state.

Sullivan has acknowledged in the past that a brokered convention might be hypothetically possible, but Wednesday’s comments are a concrete indication that the campaign is preparing for such an outcome.

Sullivan gave a “technical” explanation of how a contested or brokered convention would work. According to the sources in the room, the gathering appeared to be a matter-of-fact recognition by the Rubio campaign that a contested convention is very much a possibility.

“One is somebody – Trump or Rubio – wins enough primaries to sew up the nomination in advance of the convention,” one attendee said. “The other is that nobody does, and the two candidates go to the convention.”

On how Rubio could get the nomination before the convention, Sullivan discussed the possibilities of John Kasich and Ben Carson dropping out, that attendee also said.

Rubio spokesman Alex Conant declined to comment. Sullivan did not immediately respond to a request for comment.

Sullivan also expressed confidence that Rubio would win the Florida primary, two attendees said, despite polling showing Rubio trailing Trump in his home state.

There were close to some 200 people present at the midtown Manhattan meeting – and among them were former Jeb Bush supporters, the people present said.

Coming just days after Bush abandoned his White House bid, one question from these donors and potential bundlers – not all of whom had decided to back Rubio – was whether the Rubio team could reassure them that their money and time would not once again go to waste, according to one attendee.

“They wanted to know that we on the Rubio side are going to be good stewards,” the person said.